JPH04372376A - Nailing machine - Google Patents

Abstract

PURPOSE:To strike a nail by a number of times so as to strike the nail out with a driver installed in a striking piston by controlling a cyclic mode control valve means so as to repeat reciprocation of the striking piston. CONSTITUTION:An operation air is guided in an operation air supply route 46 by which a head valve 10 side is communicated by a trigger valve 45 following the drawing operation of a trigger 44. A head valve 10 is operated by the operation air so as to carry out supply and exhaust of compressed air to the interior of a piston of a cylinder 2, and a striking piston 8 is reciprocated for striking operation. A cyclic mode control valve means 19 is controlled so as to repeat the reciprocation of the striking piston 8, and a nail T is struck by a number of times by a driver 22 installed in the striking piston 8, and the nail is thus struck out.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nail gun that drives a nail by multiple strikes.

0002

Conventionally, in this type of nail driving machine, in order to drive a nail, the trigger is retracted and the piston is repeatedly reciprocated while the trigger is kept in motion to strike the nail many times. A structure has been devised. (for example,
Special Publication No. 57-48351, Special Publication No. 62-6957
(see publication)

0003

[Problems to be Solved by the Invention] However, in all of the above-mentioned conventional methods, the operator visually confirms the completion state of nail driving each time.
In addition, the current situation is that workers are relying on their own "kan". SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a nailing machine that can automatically confirm the completion of nail driving after multiple hits.

0004

[Means for Solving the Problem] In order to achieve the above-mentioned object, according to claim 1 of the present invention, a striking piston in a cylinder is repeatedly reciprocated and a driver installed in the striking piston is used to move the striking piston in a cylinder. In a nailing machine that drives a nail by striking it many times, there is a head valve for controlling the reciprocating movement of the striking piston, and a working air supply for introducing working air into the head valve to operate the head valve. road and
a trigger valve for controlling the supply of working air to the working air supply passage; and a repetition control valve means incorporated in the working air supply passage for repeating the reciprocating movement of the striking piston; A main control valve means is incorporated in the supply path, and this main control valve means shuts off the working air supply path by means of a detection actuation means that detects when the striking piston reaches the bottom dead center, and closes the working air supply path to the head valve side. The gist of this is that the system is configured to stop the introduction of working air into the system. According to a second aspect of the present invention, there is provided a nail driving machine that repeatedly reciprocates a striking piston in a cylinder and strikes a nail many times with a driver installed in the striking piston. A head valve for controlling the reciprocating motion of the piston, a working air supply path for introducing working air to the head valve side to operate the head valve, and controlling the supply of working air to this working air supply path. a trigger valve; and a repetitive motion control valve means incorporated in the working air supply passage for repeating reciprocating motion of the striking piston; a main control valve means incorporated in the working air supply passage; The main control valve means is connected to a detection actuation means for detecting the state in which the striking piston has reached the bottom dead center based on the difference in air pressure within the cylinder, and the main control valve means The gist of the present invention is that the working air supply path is cut off when the working air reaches the head valve side, and the introduction of working air to the head valve side is stopped. Furthermore, according to claim 3 of the present invention, in a nailing machine that drives a nail by repeatedly reciprocating a striking piston in a cylinder and striking the nail many times with a driver installed in the striking piston, the striking a head valve for controlling the reciprocating motion of the head valve, a working air supply path for introducing working air for operating the head valve into the head valve side, and a trigger valve for controlling the supply of working air to the working air supply path. ,
a repetitive motion control valve means incorporated in the working air supply passage for repeating the reciprocating motion of the striking piston; a main control valve means incorporated in the working air supply passage; the main control valve means; is connected to a detection actuation means that detects the state in which the percussion piston reaches the bottom dead center in conjunction with the operation of the percussion piston, and this main control valve means is activated when the percussion piston reaches the bottom dead center. The gist of the present invention is that the air supply path is shut off to stop the introduction of operating air to the head valve side.

[0005]

[Operation] According to claim 1 having the above-mentioned configuration, as the trigger is retracted, working air is introduced into the working air supply path communicating with the head valve side by the trigger valve, and the working air is used to The head valve is operated to supply and exhaust compressed air into the piston upper chamber of the cylinder to reciprocate the percussion piston for percussion operation, and in this state, the repetitive motion control valve means is controlled to control the percussion piston. This reciprocating motion is repeated, and the nail is driven out by striking it many times with a driver installed on the striking piston. When the striking piston reaches the bottom dead center, the state is detected by the detection actuation means, and
A main control valve means shuts off the actuation air supply path. As a result, the operation of the head valve by the working air from the working air supply path is stopped, and the striking action (reciprocating motion) of the striking piston is stopped. In other words, it is possible to automatically confirm the completion of nail driving after multiple hits. Further, in claim 2 configured as described above, when the striking piston reaches the bottom dead center, this state is detected by the difference in air pressure within the cylinder, and the main control is connected to this. Valve means is operated to shut off the working air supply path. As a result, the operation of the head valve by the working air from the working air supply path is stopped, and the striking action (reciprocating motion) of the striking piston is stopped. That is,
It is possible to automatically confirm the completion of nail driving after multiple hits. According to a third aspect of the invention configured as above, when the striking piston reaches the bottom dead center, the state is detected by the detection actuation means connected to the striking piston, and the main control valve means is thereby detected. is operated to cut off the working air supply path. Therefore, the operation of the head valve by the working air from the working air supply path is stopped, and the striking action (reciprocating motion) of the striking piston is stopped. In other words, it is possible to automatically confirm the completion of nail driving after multiple hits.

[0006]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, a first embodiment shown in FIGS. 1 to 15 will be described. In the figures, a nailing machine 1 is roughly divided into a substantially cylindrical main body 3 consisting of a housing 3b in which a cylindrical cylinder 2 is housed. and a substantially cylindrical handle portion 5 consisting of a housing formed integrally with the main body portion 3 and forming a compressed air reservoir 4 connected to a compressed air supply source (not shown) via a hose or the like. , a driver guide 6 installed below the cylinder 2 in the main body part 3, and a substantially cylindrical nail magazine part 7 installed across the driver guide 6 and the handle part 5.

A striking piston 8 is disposed inside the cylinder 2.
A flange 3a protruding from approximately the center of the outer periphery of the cylinder 2 is slidably contacted with the housing 3b so as to sealingly partition the gap formed between the cylinder 2 and the housing 3b into upper and lower sections. The upper gap is a main air chamber 11 that communicates with the piston upper chamber 9 on the head side of the cylinder 2 via a head valve 10, and the lower gap is a return air chamber 12. . This main air chamber 11 is always in communication with the compressed air reservoir chamber 4 in the handle part 5, and the return air chamber 12 allows one-way circulation through a plurality of through holes 13a provided on the side circumference of the center part of the cylinder 2. A through hole 13 that allows flow only from inside the cylinder 2 through a check valve and is provided almost at the bottom of the cylinder 2.
It communicates with the inside of the cylinder 2 via b. Further, a portion of the side portion of the piston upper chamber 9 is communicated with the atmosphere through the exhaust hole 14, and a portion of the lower portion of the return air chamber 12 is also configured to be able to communicate with the atmosphere side.

The head valve 10 has a cylindrical small diameter portion 10.
a and a cylindrical large-diameter portion 10b, the small-diameter portion 10a is fitted into a head valve chamber 16 partitioned by a partition wall 9a in the piston upper chamber 9, and the large-diameter portion 10b
is fitted into the upper end portion of the cylinder 2, and the small diameter portion 10a
A stepped surface 10c between the piston upper chamber 9 and the main air chamber 11 is opposed to the stepped surface 9b formed at the boundary between the piston upper chamber 9 and the main air chamber 11 so as to be able to abut with a sealing member interposed therebetween. There is. At the base of the small diameter part 10a and the large diameter part 10b of the head valve 10, the piston upper chamber 9 and the main air chamber 11 are connected or connected depending on the position of the head valve 10 in the piston upper chamber 9. A first communication hole 17 is provided through the piston upper chamber 9 and the exhaust hole 14 to interrupt the communication therebetween. Further, the head valve 10 is always operated by the stepped surface 10c due to the spring 18 elastically loaded between the substantially lower end surface of the large diameter portion 10b and substantially the upper portion of the outer periphery of the cylinder 2 and the compressed air pressure within the main air chamber 11. is in contact with the stepped surface 9b in the piston upper chamber 9 with a sealing member interposed therebetween, thereby blocking communication with the main air chamber 11 through the first communication hole 17 and maintaining communication with the exhaust hole 14. It is configured to Therefore, from the main air chamber 11 to the piston upper chamber 9
The striking piston 8 is moved forward (downward movement in the figure) for striking by the compressed air supplied therein, and the compressed air in the piston upper chamber 9 is discharged to the atmosphere, and the return air chamber 1
The impact piston 8 is moved back (upwards in the drawing) by the air from 2. The upper valve chamber of the head valve chamber 16 communicates with the second communication hole 15.
5 is in communication with an operating air supply path 46 via a repetitive motion control valve chamber 19, as will be described later. Note that a portion of the second communication hole 15 can communicate with the atmosphere through an extremely small diameter hole.

The second communication hole 15 and the working air supply path 4
6 is provided with a repetitive motion control valve means 19, and this repetitive motion control valve means 19 is moved downward by operating air introduced from a main control valve means 47, which will be described later. Operating air from the means 47 is introduced into the second communication hole 15 to move the head valve 10 downward (
(opening movement) and upward movement (closing movement) by the air introduced from the return air chamber 12 through the third communication hole 16a to cut off communication between the second communication hole 15 and the working air supply path 46. It is configured as follows.

A substantially ring-shaped buffer member 20 made of rubber or the like is installed on the lower end side of the cylinder 2 to cushion the impact at the bottom dead center position of the striking piston 8.
The partition wall 9 in the piston upper chamber 9 is located on the upper end side of the cylinder 2.
A substantially cap-shaped buffer member 21 made of rubber or the like is installed at the inner portion surrounded by a to cushion the impact of the striking piston 8 at the top dead center position.

A long driver 22 in the shape of a round bar is integrally installed in the striking piston 8 in a hanging manner, and a screwdriver 22 having an oblique shape in the radial direction of the striking piston 8 is provided substantially at the upper part in the axial direction of the driver 22. A substantially L-shaped second exhaust passage 24 is provided therethrough and communicates with the first exhaust passage 23 that is passed through the driver 22 , and the driver 22 is mounted in the main body 3 with its lower end portion below the cylinder 2 . Nail guide path 25 of the installed driver guide 6
It can be slid back and forth inside. The driver guide 6
A nail feed passage 26 communicating with the nail guide passage 25 is provided on the side of the nail guide passage 25.
is formed, and its starting end communicates with the nail magazine section 7 that accommodates a large number of nails connected in series. Thus, the nails T connected in series at predetermined intervals by the connecting band TW in the nail magazine section 7 are connected to the nail feeding means 3 which will be described later.
4, the nails are automatically fed one by one into the nail guide path 25 through the nail feeding path 26.

The nail guide path 25 of the driver guide 6 has an inner circumference approximately the same diameter as the head of the nail T, and has a predetermined length at approximately the lower end with the lower end surface open. A plurality of guide slits 27 to 27 are formed at equal intervals in the axial direction (the figure shows a case of three guide slits). Further, a contact arm 28 is installed on the driver guide 6 so as to be movable up and down. This contact arm 28 is a substantially cylindrical tip member 2 fitted onto the outer periphery of the tip of the driver guide 6.
9, a shaft member 30 erected from the tip member 29, and a main control valve means 47 whose one end is fitted into the shaft member 30 via a retaining ring 31a, bent upward and extended, and which will be described later. An arm member 31 located opposite to the third valve of
and a spring 32 which is wound around the shaft member 30 and is elastically loaded between the upper end surface of the tip member 29 and one end of the arm member 31 to normally bias the arm member 31 upward. The tip member 29 has guide protrusions 33 to 33 fitted into the guide slits 27 to 27 in the axial direction of the inner circumference thereof.
33 is integrally formed to protrude, and these guide protrusions 33 to 33
The inner surface of the contact arm 28 is aligned with the inner circumferential surface of the nail guide path 25 of the driver guide 6, and allows vertical movement of the entire contact arm 28 within a predetermined range. It is formed into a substantially acute angle shape that slightly protrudes from the lower end surface of 6.

Further, the nail feeding means 34 installed on the side of the driver guide 6 has a cylinder 35 formed in the same direction as the feeding direction of the nail T, and is fitted into the cylinder 35 so as to be able to reciprocate. The piston 36 and its rod 37 are composed of a substantially crank-shaped feed arm 38 which is pivoted 38a to the substantially distal end of the rod 37. The feed arm 3
8 has a bifurcated claw portion 40 that faces the nail feed passage 26 and captures the nail T, and a diagonal relief on one of the claw portions 40 side and on the back side of the other claw portion. Surfaces 41a and 41b are formed, and a stopper 42 is formed at the rear end so as to be able to come into contact with the rod 36 for maintaining the state in which the nail is captured by the claw portion 40. Further, between the feed arm 38 and the rod 37, a spring 43 is provided which biases the feed arm 38 toward the nail catching state by the claw portion 40, that is, the return rotation direction.
is loaded with ammunition. Therefore, the nail feeding means 34 always moves the nail T immediately before the nail portion 40 of the feeding arm 38 faces the nail feeding path 26 and reaches the nail guide path 25 in the nail T in the nail feeding path 26, that is, the nail It is in a position to capture the next nail T (second nail) after the nail T located in the guide path 25, and when the piston 36 and its rod 37 are moved forward by the air supplied into the cylinder 35, the feed arm 38 is moved. Using the oblique escape surfaces 41a and 41b, the third nail T is moved backward by the claw portion 40 while avoiding the second and third nails T that are captured by repeating rotation and return movement. Then, when the air supply to the cylinder 35 is stopped and the piston 36 and its rod 37 are moved back by the biasing force of the spring 39, the feed arm 38 is moved back together and the second nail T is captured. The nail T is fed into the nail guide path 25 and the third nail T captured by the claw portion 40 is positioned second, and this nail feeding operation is linked to the completion of the driving operation of one nail. This is done by

A trigger 44 is provided at the boundary between the main body portion 3 and the handle portion 5 so as to be retractable and rotatable, and one side of the trigger 44 is connected to the compressed air reservoir chamber 4 at a portion facing the trigger 44. A trigger valve 45 is installed, and the other side of the trigger valve 45 communicates with a working air supply passage 46 which communicates with the second communication hole 15 via the repetitive motion control valve means 19. It is operated in conjunction with the retracting operation of the trigger 44, and when the trigger 44 is retracted, communication between the inside of the compressed air reservoir 4 and the working air supply path 46 is allowed, and when the retracting of the trigger 44 is released, the compressed air reservoir 4 is allowed to communicate with the working air supply path 46. It is configured to cut off communication between the inside and the working air supply path 46.

The main control valve means 47 installed in the middle of the working air supply path 46 is a main control valve means 47 that opens and closes the working air supply path 46 (communication between the trigger valve 45 side and the repetitive motion control valve 19 side in the working air supply path 46). and a second valve 49 that controls the opening and closing movement of the first valve 48 and that is linked with the second valve 49 and the contact arm 28. The third
As shown in FIG. 1, the valve 50 is built into the main body 3 along the side thereof.

The first valve 48 is installed so as to be able to reciprocate (move up and down in the figure) within its valve chamber. The first piston portion 48a is located in the first valve chamber 51 communicating with the dynamic control valve 19 side, and communicates and cuts off the communication with the second valve 49 through the first passage 53. A second piston part 48b located in a second valve chamber 54 communicating with the second piston part 48b is formed, and this first valve 48 is always reciprocated ( (Illustrated below)
is energized by Note that the first valve 48 is formed with an operating air supply path 46 on the repetitive motion control valve 19 side and a through hole 56 that can communicate with the atmosphere. Further, the communication point of the first passage 53 with the second valve chamber 54 is set at the lower part of the valve chamber 54 in the figure, and a part of the upper part of the valve chamber 54 in the figure can communicate with the atmosphere. Therefore, in the upper position of the first valve 48, the trigger valve 45 of the operating air supply path 46 is activated by the first piston portion 48a.
The communication between the side and the repetitive motion control valve means 19 side is cut off, and the passage hole 56 is communicated with the atmosphere, and in the lower position, the communication between the trigger valve 45 side and the repetitive motion control valve means 19 side of the working air supply path 46 is cut off. This allows communication.

The second valve 49 is installed in the valve chamber so as to be able to reciprocate (move up and down in the figure), and is normally positioned at the lower end of the valve chamber in the figure by a spring 57, and is connected to the first annular groove from the top in the figure. 58a, a second annular groove 58b, and a third annular groove 58c are formed, and furthermore, from the lower end in the figure to the second annular groove 58b, the lower chamber 52 of the valve chamber and the second annular groove 58b are connected via a check valve 59a. A through hole 59 is provided to communicate with each other. And each annular groove 5
8a to 58c are at lower positions of the second valve 49,
A first annular groove 58a communicates with the first passage 53 and a second passage 60 that communicates with the main air chamber 11, and a second annular groove 58b communicates with the inside of the cylinder 35 of the nail feeding means 34. The third passage 61 communicates with the atmosphere, and the fourth passage 62 communicates with the atmosphere.
The annular groove 58c communicates with a fifth passage 63 that communicates with a substantially lower part of the return air chamber 12, and at the first upper position of the second valve 49, the first annular groove 58a communicates with the second passage 60. The communication state of the second annular groove 58b is maintained with the third passage 61 and the fourth passage 62, and the communication with the first passage 53 is maintained, and the communication with the first passage 53 is maintained. and the third annular groove 58c
is maintained in communication with the fifth passage 63, and the lower chamber 52 of the valve chamber and the fifth passage 63 are communicated with each other.Furthermore, at the uppermost position, the second annular groove 58b is connected to the first passage 53 and the second passage 63.
The lower chamber 52 of the valve chamber is configured to be in communication with the passage 60 and the third passage 61, the third annular groove 58c and the fourth passage 62, and the lower chamber 52 of the valve chamber is maintained in communication with the fifth passage 63. There is.

The third valve 50 has a piston 50a installed in the valve chamber 64 so as to be able to reciprocate (move up and down in the figure).
, whose upper end in the figure extends from the valve chamber 64 and is capable of moving in and out of the lower chamber 52 of the second valve 49, and is opposed to the lower end surface of the second valve 49 so as to be able to come into contact with it, and its lower end in the figure extends into the lower chamber 52 of the second valve 49. 64 and extending from the contact arm 28
are positioned opposite to the upper surface of the arm member 31 so as to be movable in conjunction with each other. The lower part of the piston lower chamber 64a in the valve chamber 64 is connected to a first air pressure sensing hole 65 provided through the cylinder 2 near the bottom dead center of the percussion piston 8 in which the percussion piston 8 reciprocates. The first air pressure sensing hole 65 near the bottom dead center of the striking piston 8 in the cylinder 2 in which the striking piston 8 reciprocates is connected to the upper piston chamber 64b. A second air control passage 68 is in communication with a second air pressure sensing hole 67 extending through the lower part. The positions of the first air pressure sensing hole 65 and the second air pressure sensing hole 67 are such that when the striking piston 8 reaches the bottom dead center in the cylinder 2, the second air pressure sensing hole 67 and the striking piston 8 are in the same position. The first exhaust passage 23 is connected to the atmosphere through the second exhaust passage 24, and the first air pressure sensing hole 65 is connected to the air in the cylinder 2. The third valve 50 is set to be communicated with the upper inner portion of the striking piston 8, that is, the third valve 50 is moved upward by the difference in air pressure acting on the first and second air pressure sensing holes 65, 67. ing. In the third valve 50, the piston 50a is normally positioned at the lowest position in the valve chamber 64, the upper end is in contact with the lower surface of the second valve 49, and the lower end extends from the valve chamber 64. and the contact arm 28
During upward movement, the piston 50a is pushed up by the arm member 31 and positioned at an upper position in the valve chamber 64 (almost in the middle of the valve chamber 64), and the piston 50a is moved upwardly into the lower chamber 64 of the valve chamber 64.
a and the first air control passage 66, and the piston upper chamber 64b and the second air control passage 66.
The air control passages 68 are communicated with each other, and the air pressure from both passages 66 and 68 is balanced and held in that position, and the second valve 49 is pushed up to the first upper position, and the striking piston 8 is When the bottom dead center in the cylinder 2 is reached and the air in the piston upper chamber 64b is exhausted to the atmosphere, the piston 50a is located at the uppermost position in the valve chamber 64, and its lower end is slightly above the arm member 31 of the contact arm 28. The second valve 49 is moved to a higher position.

Next, the operation of the nailing machine 1 of this embodiment constructed as described above will be explained. Now, compressed air reservoir chamber 4
Compressed air is supplied from a compressed air supply source (not shown) into the main air chamber 11, and the main air chamber 11 is filled with compressed air from the compressed air storage chamber 4, and the impact piston 8 is moved to the top dead center of the cylinder 2. 8, the nail T to be driven is located in the nail guide path 25 of the driver guide 6, and the next nail to be driven is located in the nail feed path 26 in sequence, the nail driving operation shown in FIG. In the front, the trigger 44 is not retracted, and the trigger valve 45 maintains a state in which communication between the compressed air reservoir 4 and the working air supply path 46 is cut off, and the contact arm 28 is closed. Since the tip member 29 is not pressed up against the surface to be driven, the second and third valves 49 and 50 of the main control valve means 47 are maintained in their lower states. In the lower state of the second valve 49 of the main control valve means 47, the first annular groove 58a is in communication with the first passage 53 and the second passage 60, so that the main air chamber 11 is compressed. Air flows through the second passage 60, the first annular groove 58a of the second valve 49,
It is introduced into the second valve chamber 54 of the first valve 48 of the main control valve means 47 through the first passage 53, and the entire first valve 48 is moved upward against the biasing force of the spring 55. While the second piston portion 48b is moved to the upper position, the first piston 48a thereof is also located at the upper position, and the communication between the trigger valve 45 side and the repetitive motion control valve means 19 side in the working air supply path 46 is maintained in a blocked state. It is something that

Further, as shown in FIG. 9, when the trigger 44 is pulled in and the trigger valve 45 communicates the compressed air reservoir 4 with the working air supply path 46, the compressed air in the compressed air reservoir 4 is released. The air flows as working air into the working air supply path 46 to the first valve 48 of the main control valve means 47 mentioned above. However, as described above, the first valve 48 is not pushed up by the tip member 29 of the contact arm 28 coming into contact with the surface to be driven, and the first valve 48 is not pushed up by the trigger valve 45 side in the working air supply path 46 and the repetitive motion control. Communication with the valve means 19 side is maintained in a blocked state. Therefore, unless the tip member 29 of the contact arm 28 is pressed up against the surface to be driven in order to drive a nail, the striking piston 8 cannot be moved downward, that is, the nail driving operation cannot be performed even if the trigger 44 is pulled in. It is.

As shown in FIG. 10, in order to drive a nail, the nail gun 1 is pushed together with the driver guide 7 by contacting the tip member 29 of the contact arm 28 against the surface to be nailed. When attached, the tip member 29 is moved upward together with the shaft member 30 while compressing the spring 32, and the arm member 31 is moved upward by the elasticity of the spring 32, so that the arm member 31 is moved upward by the upward movement of the entire contact arm 28. The third valve 50 of the main control valve means 47, which is opposite to the valve 31, is pushed up to the upper position. In this case, the tip member 29 of the contact arm 28
The upward movement of the driver guide member 6 is guided by the guide ridges 33 to 33 moving upward within the guide slits 27 to 27 of the driver guide member 6. When the third valve 50 of the main control valve means 47 is pushed up to the upper position, the piston lower chamber 64a and the piston upper chamber 64b are connected to each other via the first air control passage 66 and the second air control passage 68. They are communicated with the lower inner portion of the striking piston 8 in the cylinder 2, and control air of the same pressure in the cylinder 2 is applied thereto. On the other hand, as the third valve 50 is pushed up to the upper position, the second valve 49 is pushed up to the first upper position against the urging force of the spring 57, and the first passage 53
is communicated with the atmosphere through the second annular groove 58b and the fourth passage 62 of the second valve 49, so that the first valve 4
8 is moved downward by the biasing force of the spring 55 to move its second piston portion 48b to a lower position, and its first piston 48a is also located at a lower position, triggering a trigger in the working air supply path 46 which has been in a closed state until now. valve 45
This allows communication between the side and the repetitive motion control valve means 19 side. Note that the second valve 49 in the first upper position has its first annular groove 58a connected to the second passage 6 in addition to the above-mentioned communication state.
0, the second annular groove 58b maintains communication with both the third passage 61 and the fourth passage 62, and the third annular groove 58c communicates with the fifth passage 63. ing.

Therefore, as shown in FIG.
When the trigger valve 45 connects the compressed air reservoir 4 and the working air supply path 46 by pulling the trigger valve 45, the working air in the working air supply path 46 from the compressed air reservoir 4 is transferred to the main control valve described above. from the means 47 to the repetitive motion control valve means 19 and the repetitive motion control valve means 1
9 is moved down and introduced into the upper chamber of the head valve chamber 16 via the second communication hole 15. Since this working air acts on the head valve 10, the head valve 10 is moved downward, and the piston upper chamber 9 of the striking piston 8 and the main air chamber 11
and are brought into communication via the first communication hole 17. In this case, as the head valve 10 moves downward, the first communication hole 17
The communication between the exhaust hole 14 and the exhaust hole 14 is cut off. In the above state, from the main air chamber 11 to the piston upper chamber 9
Compressed air is supplied into the interior, and the compressed air moves the striking piston 8 downward (forward movement), and the driver 22 integrated with the movable striking piston 8 drives the nail T in the nail guide path 25 of the driver guide 6. It is something to put out. As the striking piston 8 moves downward, the compressed air in the cylinder 2 at the lower part of the striking piston 8 flows into the return air chamber 12 through the through holes 13a and 13b.

As shown in FIG. 12, the striking piston 8 reaches the lower end for the first striking, and the compressed air from the return air chamber 12 enters the repetitive action control valve means 19 through the third communication hole. 16a, the repetitive motion control valve means 19 moves upward to cut off communication between the second communication hole 15 and the working air supply path 46. On the other hand, in the head valve 10, a part of the second communication hole 15 is in communication with the atmosphere through an extremely small diameter hole, and compressed air in the main air chamber 11 always acts on its pressure receiving surface. This causes the first communication hole 17 to communicate with the exhaust hole 14 while blocking communication with the main air chamber 11, thereby discharging the compressed air in the piston upper chamber 9 to the atmosphere. Therefore, the striking piston 8 has a return air chamber 12
It is moved upward (backwards) by compressed air from the and,
When the striking piston 8 reaches the upper moving end (top dead center), the air inside the lower part of the striking piston 8 in the cylinder 2 is exhausted to the atmosphere from the hole on the tip side of the driver 22, so that the third communication The pressure on the hole 16a side becomes low, and as a result, the repetitive motion control valve means 19 is again moved downward by the working air to bring the second communication hole 15 and the working air supply path 46 into communication, and the head valve 10 is closed as described above. , the striking piston 8 is moved downward for the second striking. Thereafter, the upward and downward movements of the striking piston 8 (
The reciprocating motion) is repeated several times by the operation of the repetitive motion control valve means 19, and the nail T is struck and driven many times. In the above state, air of the same pressure from the lower inner portion of the striking piston 8 in the cylinder 2 acts on both the first air pressure sensing hole 65 and the second air pressure sensing hole 67. The third valve 50 in the control valve means 47 has a lower piston chamber 64a that communicates with the first air control passage 66 and an upper piston chamber 64b that communicates with the second air control passage 68, which are balanced. The position of the object is maintained.

Then, as shown in FIG. 13, when the striking piston 8 moves as described above and reaches the bottom dead center in the cylinder 2, and the nail T is completely driven from the driver guide 6 into the surface to be driven, The control air in the upper inner part of the striking piston 8 in the cylinder 2 is passed through the first air control passage 66 by the first air pressure sensing hole 65 to the piston in the valve chamber 64 of the third valve 50 in the main control valve means 47. lower chamber 6
4a. On the other hand, communication with the inside of the cylinder 2 is cut off by the striking piston 8 in which the second air pressure sensing hole 67 is located at the bottom dead center, and the first exhaust passage 23 formed in the striking piston 8 and the second exhaust Since it is communicated with the atmosphere through the passage 24, the air in the piston upper chamber 64b of the valve chamber 64 of the third valve 50 in the main control valve means 47 is connected to the second control passage 68, the second air pressure sensing hole 67, It is exhausted to the atmosphere from both exhaust passages 23 and 24. by this,
The air pressure balance between the piston lower chamber 64a and the piston upper chamber 64b of the third valve 50 is lost, causing the piston 5
0a is moved upwardly to the uppermost position in the valve chamber 64 by the control air introduced into the piston lower chamber 64a, and its lower end is separated from the arm member 31 of the contact arm 28 and moved to the second position.
The valve 49 is pushed up from the first upper position to a higher position. Then, when the second valve 49 is pushed up as described above, the second annular groove 58b
is communicated with the third passage 61 while maintaining communication with the first passage 53, and the lower chamber 52 of the valve chamber and the fifth passage 6
Since the compressed air from the return air chamber 12 is introduced into the lower chamber 52 of the valve chamber, the second valve 49 is gradually moved upward to the uppermost position.

The head TH of the nail T driven out from the driver guide 6 is guided by the inner peripheral surface of the nail guide path 25 of the driver guide 6, and near the tip, the nail T is guided by the inner peripheral surface of the nail guide path 25 of the driver guide 6. Guide protrusions 33 - of the tip member 29 of the contact arm 28 fitted into the surfaces and guide slits 27 - 27
The head TH of the nail T is guided by the inner surface of the nail T 33 and only by the inner surface of the guide protrusions 33 to 33 of the tip member 29 in a portion away from the tip of the nail guide path 25. T guides the nail guide protrusions 33 to 33 in a straight state.

[0026] Then, as described above, the second valve 4
9 is located at the top, as shown in FIG. 14, the second annular groove 58b of the second valve 49 is maintained in communication with the first passage 53 and the third passage 61, and the second The second valve chamber 54 of the first valve 48 of the main control valve means 47 has a main air chamber 1 in communication with the passage 60 .
The compressed air in the second passage 60, the second annular groove 58b,
is introduced through the first passage 53, and the entire first valve 48 is moved upward against the biasing force of the spring 55, moving its second piston portion 48b to the upper state and moving its first valve 48 upward.
The piston 48a is also located at the upper position and the working air supply path 4
6, the communication between the trigger valve 45 side and the repetitive motion control valve means 19 side is cut off. Then, the working air in the working air supply path 46 communicating with the repetitive action control valve means 19 side (second communication hole 15 side) flows into the first valve of the main control valve means 47.
The working air in the upper chamber of the head valve chamber 16 is also exhausted from the second communication hole 15 through the working air supply path 46, so that the working air in the head valve chamber 16 is exhausted to the atmosphere through the through hole 56 of the valve 48. The pressure inside the upper chamber 16 becomes low, and as a result, the head valve 10 is moved upward as described above, and its first communication hole 17 is communicated with the exhaust hole 14 while cutting off communication with the main air chamber 11, and the piston The compressed air in the upper chamber 9 is discharged to the atmosphere. Therefore, the striking piston 8
is moved upward (backwards) by compressed air from the return air chamber 12 to reach the top dead center, and that position is maintained. At this point, the driving operation by repeatedly hitting the first nail T is completed, and without releasing the retracting operation of the trigger 44, the driving operation is completed by pressing the cylinder at the bottom dead center of the hitting piston 8. The main control valve means 47 is controlled by the air pressure in the main control valve 47 to automatically confirm the condition. In this case, the repetitive motion control valve means 19 is moved upward by the compressed air from the return air chamber 12 as described above to cut off the communication between the second communication hole 15 and the working air supply path 46, This position is maintained unless working air is supplied into the air supply path 46.

As described above, when the driving operation of the first nail T by repeatedly hitting the nail T is completed, the second valve 49 of the main control valve means 47 is activated in synchronization with this.
is in the uppermost position, the second annular groove 58b is connected to the first passage 53, the second passage 60, and the third passage 6.
1, the compressed air in the main air chamber 11 is supplied from the second passage 60 and the second annular groove 58b to the third passage 61 and into the cylinder 35 of the nail feeding means 34, so that the piston 36 and rod 37 are moved forward within the cylinder 35. Due to this forward movement of the rod 3, the feed arm 38 uses its oblique release surfaces 41a and 41b to repeatedly rotate and return due to the biasing force of the spring 43, thereby capturing the second nail T and the third nail. While avoiding the third nail T, the third nail T is captured by the claw portion 40. Then, as described above, when the striking piston 8 reaches the top dead center from the upward movement, the first air pressure sensing hole 65 and the second air pressure sensing hole 67 are opened as shown in FIG. Air of the same pressure in the lower inner part of the striking piston 8 in the cylinder 2 acts on the main control valve means 47.
The third valve 50 in is moved back to the upper position. On the other hand, the air in the lower part of the striking piston 8 in the cylinder 2 is exhausted to the atmosphere from the hole on the tip side of the driver 22, and the inside of the return air chamber 12 is in a low pressure state, so the main control valve means 47, the second valve 49 is moved down to the first upper position by the biasing force of the spring 57 so that its lower end comes into contact with the third valve 50. Then, the inside of the cylinder 35 of the nail feeding means 34 is communicated with the atmosphere through the third passage 61, the second annular groove 58b, and the fourth passage 62, so that the piston 36 and its rod 37 inside the cylinder 35 are moved by the spring 39. At the same time, the feeding arm 38 is moved back together with the biasing force to feed the second nail T into the nail guide path 25, and the third nail T captured by the claw portion 40 is moved back to the second position. As a result, the nail T positioned second to the front is automatically fed into the nail guide path 25 of the driver guide member 6. Note that when the second valve 49 in the main control valve means 47 moves downward, the air in the lower chamber 52 of the valve chamber passes through the through hole 59 and the check valve 59a, and then flows into the second annular groove 58b and into the fourth annular groove 58b. It is exhausted to the atmosphere from the passage 62.

Then, the nailer 1 is moved together with the driver guide 6 against the surface to be nailed, and the tip member 29 of the contact arm 28 is released from being pressed, and the main control valve means 47 is controlled by the arm member 31. When the third valve 50 is released from being pushed up, the main control valve means 47
By returning the valves 48, 49, and 50 to their original states, and further releasing the retracting operation of the trigger 44, communication between the compressed air reservoir 4 and the working air supply path 46 is cut off.

Next, a second embodiment shown in FIGS. 16 to 23 will be explained. This embodiment is similar to the main control valve means 47 and the first and second air sensing holes 6 of the first embodiment described above.
5, 67 and the cylinder 2 is changed, and the rest of the configuration is the same as the first embodiment.
For the same configuration, A is added after the same reference numeral in the drawings (for example, in the case of nailing machine 1, it is written as nailing machine 1A), and the explanation thereof will be omitted.

That is, as shown in FIG. 17, the main control valve means 47A installed in the nailing machine 1A as in the previous example has a configuration in which the third valve 50 of the previous example is omitted, and the first
formed from a valve 48A and a second valve 49A,
This first valve 48A has the same structure as the previous example, and is installed so as to be able to reciprocate (move up and down in the figure) within the valve chamber. The valve chambers of the first piston part 48a and the second valve 49A, which are located in the first valve chamber 51A communicating with the 45A side and the repetitive motion control valve means 19A side, and which communicate and cut off the communication with each other. A second piston portion 48b located within the second valve chamber 54A communicating through the first passage 53A is formed, and the first
The valve 48A is always urged downward in the drawing by a spring 55A elastically mounted on the second piston portion 48b side. Note that the first valve 48A has a through hole 5 that communicates with the operating air supply path 46A on the repetitive motion control valve 19A side.
6A is formed so that the through hole 56A can communicate with the atmosphere. Further, the point of communication of the first passage 53A with the second valve chamber 54A is set at the lower part of the valve chamber 54A in the figure, and a part of the upper part of the valve chamber 54A in the figure is communicated with the atmosphere. Therefore, in the upper position of the first valve 48A, the first piston portion 48a blocks communication between the trigger valve 45A side and the repetitive motion control valve 19A side of the operating air supply path 46A, and the passage hole 56A is opened to the atmosphere. The working air supply path 46 is in communication with the working air supply path 46 in the lower position.
This allows communication between the trigger valve 45A side of A and the repetitive motion control valve 19A side.

The second valve 49A is installed in the valve chamber so as to be able to reciprocate (move up and down in the figure), and is normally positioned at the lower end of the valve chamber 52A in the figure by means of a spring 57A. 58a, second annular groove 58b,
A third annular groove 58c is formed, the lower end of which extends downward from the lower chamber 52A of the valve chamber and is opposed to the arm member 31A of the contact arm 28A so as to be capable of pushing up. And each annular groove 58a
~58c is located at a lower position of the second valve 49A, and the first annular groove 58a communicates with a second passage 60A that communicates with the main air chamber 11A and a second air control passage 68A on the working air chamber 71 side, which will be described later. and the first passage 53A
The second annular groove 58b communicates with the third passage 61A, which communicates with the inside of the cylinder 35A of the nail feeding means 34A, and communicates with the atmosphere via the fourth passage 62A, and the third annular groove 58c communicates with the atmosphere. It communicates with a fifth passage 63A that communicates with the substantially lower part of the air chamber 12A, and as the contact arm 28A moves upward, its arm member 31A
At the first upper position of the second valve 49A pushed up by The groove 58b is maintained in communication with both the third passage 61A and the fourth passage 62A and communicated with the first passage 53A, the third annular groove 58c is communicated with the fifth passage 63A, and the lower chamber 52A of the valve chamber is communicated with a first air control passage 66A on the working air chamber 71 side, which will be described later, and furthermore, at the uppermost position, a second annular groove 58b
are in communication with the first passage 53A, the second passage 60A, and the third passage 61A, respectively, and the third annular groove 58c is connected to the fourth passage 62A.
The lower chamber 52A of the valve chamber communicates with the fifth passage 63A.
and the first air control passage 66A.

[0032] A working air chamber 7 is located below the cylinder 2A.
1 is formed, and a piston 72 is loosely inserted into the air chamber so as to be able to move up and down, and the upper end of the operating rod 73 passes through the upper lower buffer member 20A to close the cylinder 2.
The actuating rod 73 is pushed down by the striking piston 8A and reaches the lower part of the air chamber 71 when the striking piston 8A reaches the bottom dead center. A first air pressure sensing hole 65A is formed above the air chamber 71, that is, at the insertion site of the operating rod 73, and the first air pressure sensing hole 65A is connected to the first air control passage 66.
A, and a second air pressure sensing hole 67 is located below.
A is formed, and the second air pressure sensing hole 67A is connected to the second air pressure sensing hole 67A.
It communicates with a second air control passage 68 that communicates with the passage 60A.

Therefore, in this embodiment, FIG.
Before the nail driving operation shown in Figure 4, trigger 4 is pressed as in the previous example.
4A pull-in operation is not performed, trigger valve 4
5A connects the compressed air reservoir chamber 4A and the working air supply path 46.
A is maintained in a state where communication with A is cut off, and the tip member 29A of the contact arm 28A is not pressed up against the surface to be driven, so the second valve 49A of the main control valve means 47A is in the lower state. is maintained. In the lower state of the second valve 49A of the main control valve means 47A, the first annular groove 58a and the first
Since the passage 53A and the second passage 60A are in communication with each other, the compressed air in the main air chamber 11A is transferred to the second passage 6.
0A, the first annular groove 49a of the second valve 49A, and the first passage 53A- are introduced into the second valve chamber 54A of the first valve 48A of the main control valve means 47A, and the entire first valve 48A is is moved upward against the biasing force of the spring 55A to move its second piston portion 48b to an upper position, and its first piston 48a is also located at the upper position, so that the trigger valve 45A in the working air supply path 46A is moved upward.
The communication between the side and the repetitive motion control valve means 19A side is maintained in a blocked state. Compressed air from the main air chamber 11A is supplied to the working air chamber 71 by a second air control passage 68A communicating with the second passage 60A, and the working rod 73 is located above the piston 72 and its upper end is The part faces into the cylinder 2A.

As shown in FIG. 19, for driving nails, the nail gun 1A is moved along with the driver guide 6A to the surface to be nailed, and the contact arm 28A is
When the tip member 29A of
The second valve 49A is pushed up to the first upper position. When the second valve 49A of the main control valve means 47A is pushed up to the first upper position, the first passage 53A passes through the second annular groove 58b of the second valve 49A and the fourth passage 62A to the atmosphere. Since the first
The valve 48A is moved downward by the urging force of the spring 55A, and its second piston portion 48b is moved to the lower position, and the first piston 48a is also positioned lower, and the working air supply path 46A, which has been in the closed state, is moved downward. This allows communication between the trigger valve 45A side and the repetitive motion control valve means 19A side.

Therefore, as shown in FIG. 20, the trigger 44
When A is pulled in and the trigger valve 45A communicates the compressed air reservoir 4A with the working air supply passage 46A, the working air in the working air supply passage 46A from the compressed air reservoir 4A is supplied to the main control valve means. 47A into the repetitive motion control valve means 19A, the repetitive motion control valve means 19A is moved downward by the operating air to permit communication between the second communication hole 15A and the operating air supply path 46A. Therefore, as in the previous example, the head valve 10A is moved downward to bring the piston upper chamber 9A above the striking piston 8A into communication with the main air chamber 11A through the first communication hole 17A. In the above state, compressed air is supplied from the main air chamber 11A into the piston upper chamber 9A, and the percussion piston 8A is moved downward (forward movement) by this compressed air, and the driver 22A, which moves downward together with the percussion piston 8A, is driven by the driver 22A. This is for driving out the nail T in the nail guide path 25A of the guide 6A. And, like the previous example, the striking piston 8A
is moved upward by compressed air from the return air chamber 12A (
The ball is moved backward), reaches the top end of movement (top dead center), and is moved downward again for the second blow. Thereafter, the upward and downward movements (reciprocating movements) of the striking piston 8A are repeated several times to drive the nail T by striking it many times.

As shown in FIG. 21, when the striking piston 8A reaches the bottom dead center in the cylinder 2 and completes driving the nail T from the driver guide 6A into the surface to be driven, the striking piston 8A releases the working air. The actuating rod 73 of the chamber 71 is pushed down together with the piston 72. Then, the working air chamber 71 is connected to the first and second air sensing holes 65A.
, 67A, the main air chamber 11
A compressed air is supplied to the second air control passage 68A, the second air sensing hole 67A, the working air chamber 71, and the first air sensing hole 65A.
, the main control valve means 47 via the first air control passage 66A.
Lower chamber 52 of the valve chamber of the second valve 49A in A
introduced into A. As a result, the second valve 49A
is further pushed up and placed at the top. At this time, the lower chamber 52A of the valve chamber of the second valve 49A is the fifth valve chamber.
It transitions to a state of communication with the passage 63A.

Next, when the second valve 49A mentioned above is positioned at the uppermost position, as shown in FIG. 22, the second annular groove 58b connects the first passage 53A, the second passage 60A,
The second valve chamber 5 of the first valve 48A of the main control valve means 47A is connected to the third passage 61A.
Compressed air from the main air chamber 11A is introduced into the main air chamber 4A through the second passage 60A and the second annular groove 58b through the first passage 53A, and the entire first valve 48A is raised against the biasing force of the spring 55A. The second piston portion 48b is moved to the upper position, and the first piston 48a is also located at the upper position, cutting off communication between the trigger valve 45A side and the repetitive motion control valve means 19A side in the working air supply path 46A. do. Then, in the same way as in the previous example, the working air in the working air supply path 46A that communicates with the repetitive motion control valve means 19A side (second communication hole 15A side) flows through the first valve 48A of the main control valve means 47A. 56A to the atmosphere, and the working air in the upper chamber of the head valve chamber 16A is also discharged from the second communication hole 15A to the working air supply path 4.
6A, the pressure inside the upper chamber of the head valve chamber 16A becomes low, thereby causing the head valve 10
A is moved upward as described above, and its first communication hole 17A opens the exhaust hole 14 while cutting off communication with the main air chamber 11A.
A and discharges the compressed air in the piston upper chamber 9A to the atmosphere. Therefore, the striking piston 8A is moved upward (backwards) by the compressed air from the return air chamber 12A, reaches the top dead center, and maintains that position. At this point, the driving operation by repeatedly hitting the first nail T is completed, and the driving operation is completed by operating the hitting piston 8A at the bottom dead center without releasing the retracting operation of the trigger 44A. This is automatically confirmed by controlling the main control valve means 47 by controlling the air in the air chamber 71. In this case as well, as in the previous example, the repetitive motion control valve means 19A is moved upward by the compressed air from the return air chamber 12A as described above to open the second communication hole 1.
5A and the working air supply path 46A, and this position is maintained unless working air is supplied into the working air supply path 46A.

On the other hand, the second valve 49A is in the uppermost position, and as the striking piston 8A moves upward, the operating rod 73 in the working air chamber 71 is in the lower position together with the piston 72. When the second valve 49A returns to the lower chamber 52A of the valve chamber, the introduction of air to the lower chamber 52A of the valve chamber of the second valve 49A is cut off, and the second valve 49A attempts to move downward. Since the fifth passage 63A is communicated with the lower chamber 52A of the valve chamber and the air in the return air chamber 12A is introduced, the downward movement of the second valve 49A is prevented, that is, the second valve 49A is prevented from moving downward. In order to temporarily hold the top level, the second
The annular groove 58b is connected to the first passage 53A, the second passage 60A, and the third passage.
The main air chamber 1 is connected to the passage 61A.
1A of compressed air flows through the second passage 60A and the second annular groove 58b.
A is supplied through the third passage 61A into the cylinder 35 of the nail feeding means 34A, and the nail feeding means 34A operates in the same manner as in the previous example to automatically feed the next nail T to be driven. (See Figures 22 and 23)

Then, the nailer 1A is moved together with the driver guide 6A to the surface to be nailed, and the tip member 29A of the contact arm 28A is released from being pressed, and the main control valve means 47A is controlled by the arm member 31A. When the push-up of the second valve 49A is released, both valves 48A and 49A of the main control valve means 47A return to their original states, and further, as shown in FIG. 23, by releasing the retracting operation of the trigger 44A, Communication between the compressed air reservoir 4A and the working air supply path 46A is cut off.

In both of the embodiments described above, the state of the bottom dead center of the striking piston 8 is determined by the first and second air pressure detection holes 65, 6 relative to the cylinder 2 as shown in the first embodiment.
The third valve 50 of the main control valve means 47 is configured to be operated by the difference in air pressure depending on the state of the striking piston 8 in the cylinder 2 which forms the air pressure detection holes 65 and 67 and acts on the air pressure detection holes 65 and 67, Further, as shown in the second embodiment, a working air chamber 71 is provided, and the working rod 7 of this working air chamber 71 is
3 is configured to be actuated by the striking piston 2, but the invention is not necessarily limited to these configurations. Any detection actuation means may be used as long as it is configured to mechanically link the state where the piston 8 has reached the bottom dead center with the striking piston 8. Further, the nail T is not limited to what is illustrated.

[0041]

As described above, in the present invention, working air is introduced into the working air supply path communicating with the head valve side by the trigger valve as the trigger is retracted, and this working air is The head valve is operated to supply and exhaust compressed air into the piston upper chamber of the cylinder to reciprocate the striking piston for a striking operation, and in this state, the repetitive motion control valve means is controlled to By repeatedly reciprocating the striking piston, the nail can be driven out by striking it many times with a driver installed on the striking piston. When the striking piston reaches the bottom dead center, the detection and actuation means detects this state, and the main control valve means shuts off the working air supply path, so that the head valve is operated by the working air from the working air supply path. Stop the operation of the striking piston (
(reciprocating motion). In other words, it is possible to automatically confirm the completion of nail driving after multiple hits. This has a simple structure, and the main control valve means is controlled by a detection actuation means that detects the state at the bottom dead center of the striking piston to indicate the end of the driving operation, and the end (completion) of nail driving after multiple strikes is automatically completed. can be confirmed. In addition, in a configuration in which the reaching of the striking piston to the bottom dead center is detected by a difference in air pressure within the cylinder, the main control valve means is thereby operated to shut off the operating air supply path; By stopping the operation of the head valve by the working air from the working air supply path, it is possible to stop the striking action (reciprocating motion) of the striking piston. That is, the condition at the bottom dead center of the striking piston can be detected by the difference in air pressure within the cylinder, and this means that the structure can be simplified as described above, and the nail driving can be completed (completed) by multiple strikes. can be automatically confirmed. In a configuration in which the reaching of the striking piston to the bottom dead center is detected by a detection actuation means connected to the striking piston, the main control valve means is thereby operated to cut off the working air supply path, By stopping the operation of the head valve by the working air from the working air supply path, the striking action (reciprocating motion) of the striking piston can be stopped. That is, the structure can be simplified and automatic stop confirmation control can be ensured.

[Brief explanation of drawings]

FIG. 1 is a front view of the entire nailing machine showing a first embodiment of the present invention.

FIG. 2 is a rear view of the entire nailing machine with some parts omitted.

FIG. 3 is an enlarged cross-sectional view showing the tip member of the contact arm.

FIG. 4 is an enlarged sectional view taken along line XX in FIG. 3;

FIG. 5 is an enlarged partially broken sectional view showing the upper part of the cylinder.

FIG. 6 is an enlarged partially broken sectional view showing the main control valve means.

FIG. 7 is an enlarged partially broken sectional view showing the nail feeding means.

FIG. 8 is an operation explanatory diagram showing a state before the nail driving operation.

FIG. 9 is an operation explanatory diagram showing a state before the nail driving operation.

FIG. 10 is an operation explanatory diagram showing a state before the nail driving operation.

FIG. 11 is an operation explanatory diagram showing a state in which the nail driving operation is started.

FIG. 12 is an operation explanatory diagram showing the upward movement state of the striking piston in the nail driving operation.

FIG. 13 is an operation explanatory diagram showing the bottom dead center state of the striking piston in the nail driving operation.

FIG. 14 is an explanatory diagram of the operation of the nail feeding means in the bottom dead center state of the striking piston.

FIG. 15 is an operation explanatory diagram showing the upward movement state of the striking piston in the nail driving operation.

FIG. 16 is an enlarged partially broken sectional view showing a working air chamber of a second embodiment of the present invention.

FIG. 17 is an enlarged partially broken sectional view showing the main control valve means.

FIG. 18 is an operation explanatory diagram showing a state before the nail driving operation.

FIG. 19 is an operation explanatory diagram showing a state in which the nail driving operation is started.

FIG. 20 is an operation explanatory diagram showing the downward movement state of the striking piston in the nail driving operation.

FIG. 21 is an operation explanatory diagram showing the bottom dead center state of the striking piston in the nail driving operation.

FIG. 22 is an operation explanatory diagram showing the bottom dead center state of the striking piston in the nail driving operation.

FIG. 23 is an operation explanatory diagram showing the upward movement state of the striking piston in the nail driving operation.

[Explanation of symbols]

1 Nailer 2 Cylinder 6 Driver guide material 8. Impact piston 10 Head valve 11 Main air chamber 19 Repetitive motion control valve means 22 Driver 44 Trigger 45 Trigger valve 46 Working air supply path 47 Main control valve means 65 First air pressure sensing hole 66 First air control passage 67 Second air pressure sensing hole 68 Second air control passage 71 Working air chamber 73 Operating rod

Claims (3)

[Claims] 1. In a nailing machine that repeatedly reciprocates a striking piston in a cylinder and drives a nail by striking it multiple times with a driver installed in the striking piston, the nailer is configured to control the reciprocating movement of the striking piston. a head valve, a working air supply path that introduces working air to the head valve side for operating the head valve, a trigger valve that controls the supply of working air to the working air supply path, and the working air supply. a repetitive motion control valve means incorporated in the passageway for repeating the reciprocating motion of the striking piston, and a main control valve means is incorporated in the working air supply passage, and this main control valve means A nailing machine characterized in that the operating air supply path is cut off by a detection actuation means that detects when the piston has reached the bottom dead center, thereby stopping the introduction of operating air to the head valve side. . 2. In a nailing machine that repeatedly reciprocates a percussion piston in a cylinder and drives a nail by striking it multiple times with a driver installed in the percussion piston, for controlling the reciprocation of the percussion piston. a head valve, a working air supply path that introduces working air to the head valve side for operating the head valve, a trigger valve that controls the supply of working air to the working air supply path, and the working air supply. a repetitive motion control valve means incorporated in the passageway for repeating the reciprocating motion of the striking piston; a main control valve means incorporated in the working air supply passage; The main control valve means is connected to a detection actuation means that detects the state in which the striking piston has reached the bottom dead center based on the difference in air pressure within the cylinder, and this main control valve means is connected to the actuation air supply path when the striking piston reaches the bottom dead center. A nailing machine characterized in that the nailing machine is configured to shut off and stop the introduction of operating air to the head valve side. 3. In a nailing machine that repeatedly reciprocates a percussion piston in a cylinder and drives a nail by striking it multiple times with a driver installed in the percussion piston, the reciprocation of the percussion piston is controlled. a head valve, a working air supply path that introduces working air to the head valve side for operating the head valve, a trigger valve that controls the supply of working air to the working air supply path, and the working air supply. a repetitive motion control valve means incorporated in the passageway for repeating the reciprocating motion of the striking piston; a main control valve means incorporated in the working air supply passage; The main control valve means is connected to a detection actuating means for detecting the state in which the striking piston has reached the bottom dead center in conjunction with the operation of the striking piston, and the main control valve means is connected to the operating air supply path when the striking piston reaches the bottom dead center. A nailing machine characterized in that the nailing machine is configured to shut off and stop the introduction of operating air to the head valve side.